<?php
/**
 * Created by PhpStorm.
 * User: cristiano
 * Date: 26/08/19
 * Time: 23.20
 */

class Upload_Filename
{

    protected function __construct()
    {
    }

    /**
     * Ritorno un'istanza dell'oggetto
     * @return Upload_Filename
     */
    public function create()
    {
        $instance = new self();
        return $instance;
    }

    public function filter($filename, $beautify = true)
    {
        // sanitize filename
        $filename = preg_replace(
            '~
        [<>:"/\\|?*]|            # file system reserved https://en.wikipedia.org/wiki/Filename#Reserved_characters_and_words
        [\x00-\x1F]|             # control characters http://msdn.microsoft.com/en-us/library/windows/desktop/aa365247%28v=vs.85%29.aspx
        [\x7F\xA0\xAD]|          # non-printing characters DEL, NO-BREAK SPACE, SOFT HYPHEN
        [#\[\]@!$&\'()+,;=]|     # URI reserved https://tools.ietf.org/html/rfc3986#section-2.2
        [{}^\~`]                 # URL unsafe characters https://www.ietf.org/rfc/rfc1738.txt
        ~x',
            '-', $filename);
        // avoids ".", ".." or ".hiddenFiles"
        $filename = ltrim($filename, '.-');
        // optional beautification
        if ($beautify) $filename = $this->beautify_filename($filename);
        // maximize filename length to 255 bytes http://serverfault.com/a/9548/44086
        $ext = pathinfo($filename, PATHINFO_EXTENSION);
        $filename = mb_strcut(pathinfo($filename, PATHINFO_FILENAME), 0, 255 - ($ext ? strlen($ext) + 1 : 0), mb_detect_encoding($filename)) . ($ext ? '.' . $ext : '');
        return $filename;
    }

    public function beautify_filename($filename) {
        // reduce consecutive characters
        $filename = preg_replace(array(
            // "file   name.zip" becomes "file-name.zip"
            '/ +/',
            // "file___name.zip" becomes "file-name.zip"
            '/_+/',
            // "file---name.zip" becomes "file-name.zip"
            '/-+/'
        ), '-', $filename);
        $filename = preg_replace(array(
            // "file--.--.-.--name.zip" becomes "file.name.zip"
            '/-*\.-*/',
            // "file...name..zip" becomes "file.name.zip"
            '/\.{2,}/'
        ), '.', $filename);
        // lowercase for windows/unix interoperability http://support.microsoft.com/kb/100625
        $filename = mb_strtolower($filename, mb_detect_encoding($filename));
        // ".file-name.-" becomes "file-name"
        $filename = trim($filename, '.-');
        return $filename;
    }
}